superprismatic Posted August 3, 2009 Report Share Posted August 3, 2009 On a TV stunt show, a couple is given the sequence of numbers 8,7,2,1,4,10,6,11,12,9,3,5 and required to straighten them out in the following way. The husband is to interchange pairs of numbers, never touching the same number twice. His wife is then to take the sequence her husband leaves and also make interchanges of numbers, again without touching the same number twice. When she finishes, the numbers are to be in order from 1 to 12. The husband begins by switching 1 and 8; how should he continue? SUPERPRISMATIC NOTE: No information is either provided or implied about the number of swaps each makes. Also, "Touching" a number means using it in a swap. When the wife's turn begins, she is allowed to touch any or all of the numbers of the sequence she inherits from her husband's turn, but no more than once each. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted August 3, 2009 Report Share Posted August 3, 2009 quote name='superprismatic' date='03 August 2009 - 03:30 PM' timestamp='1249331439' post='191776'] On a TV stunt show, a couple is given the sequence of numbers 8,7,2,1,4,10,6,11,12,9,3,5 and required to straighten them out in the following way. The husband is to interchange pairs of numbers, never touching the same number twice. His wife is then to take the sequence her husband leaves and also make interchanges of numbers, again without touching the same number twice. When she finishes, the numbers are to be in order from 1 to 12. The husband begins by switching 1 and 8; how should he continue? SUPERPRISMATIC NOTE: No information is either provided or implied about the number of swaps each makes. Also, "Touching" a number means using it in a swap. When the wife's turn begins, she is allowed to touch any or all of the numbers of the sequence she inherits from her husband's turn, but no more than once each. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted August 3, 2009 Report Share Posted August 3, 2009 Husband then swaps (7,9),(2,12),(4,11),(10,6),(3,5) Then Wife swaps (2,9),(3,12),(4,8),(5,11),(7,10) Quote Link to comment Share on other sites More sharing options...
0 Guest Posted August 3, 2009 Report Share Posted August 3, 2009 The husband should leave 1, 9, 12, 8, 11, 6, 10, 4, 2, 7, 5, 3. Quote Link to comment Share on other sites More sharing options...
0 Guest Posted August 3, 2009 Report Share Posted August 3, 2009 Husband: 1x8, 7x9, 12x2, 11x4, 6x10, 5x3 leaving 1 9 12 8 11 6 10 4 2 7 5 3 Wife: 2x9, 3x12, 4x8, 5x11, 10x7 leaving 1 2 3 4 5 6 7 8 9 10 11 12 You can start with any number putting it in the correct place... For example: original series: 8,7,2,1,4,10,6,11,12,9,3,5. I will start putting 4 in the correct place so: Me: 1x4,5x8,7x6,2x10,11x12,3x9 leaving 5 6 10 4 1 2 7 12 11 3 9 8 My wife: 1x5,2x6,3x10,8x12,9x11 leaving 1 2 3 4 5 6 7 8 9 10 11 12 The trick is always follow the number you carry from the first position. In SUPERPRISMATIC case you have to follow the 8 that falls in position 4. Therefore you have to put 4 in 8th position and so on Quote Link to comment Share on other sites More sharing options...
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superprismatic
On a TV stunt show, a couple is given the
sequence of numbers 8,7,2,1,4,10,6,11,12,9,3,5
and required to straighten them out in the
following way. The husband is to interchange
pairs of numbers, never touching the same
number twice. His wife is then to take the
sequence her husband leaves and also make
interchanges of numbers, again without touching
the same number twice. When she finishes, the
numbers are to be in order from 1 to 12. The
husband begins by switching 1 and 8; how
should he continue?
SUPERPRISMATIC NOTE: No information is either
provided or implied about the number of swaps
each makes. Also, "Touching" a number means
using it in a swap. When the wife's turn begins,
she is allowed to touch any or all of the numbers
of the sequence she inherits from her husband's
turn, but no more than once each.
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